I am able to send text through nRF24L01 but can't send an struct

Projects Networking, Protocols, and Devices
1

I have an Arduino Pro Micro + mpu-9250 + nRF24L01 mounted on a pcb and and I'm transmitting data to an arduino uno + nRF24L01 connected to the computer. With the following code I'm able to print the text on the computer screen, but not able to print the mpu data. I get this in the serial monitor:

monitor.png
monitor.png774×465 20.1 KB

Rcptr.ino (1.33 KB)

Transmissor.ino (1.65 KB)

monitor.png
monitor.png774×465 20.1 KB

2

You are using it bad..
At Transmitter and also at Receiver side.
Try my verified examples and edit them for your usage :slight_smile:

Transmitter code example with struct:

//Autor: Martin Chlebovec (martinius96)
//Web: http://arduino.clanweb.eu/

#include <SPI.h>
#include "RF24.h"
#define CE 4
#define CS 3
RF24 nRF(CE, CS);

typedef struct {
int T;
float A;
} dataPacket;

byte adresaPrijimac[] = "prijimac00";
byte adresaVysilac[] = "vysilac00";
void setup() {
Serial.begin(9600);
nRF.begin();
nRF.setDataRate( RF24_250KBPS );
nRF.setPALevel(RF24_PA_LOW);
nRF.openWritingPipe(adresaVysilac);
nRF.openReadingPipe(1, adresaPrijimac);
nRF.startListening();
}

void loop() {
dataPacket packet;
packet.T = 100;
packet.A = 3.14;
nRF.stopListening();
nRF.write(&packet, sizeof(dataPacket));
nRF.startListening();
while (nRF.available()) {
nRF.read(&packet, sizeof(dataPacket));
Serial.print("Prijata hodnota T: ");
Serial.println(packet.T);
Serial.print("Prijata hodnota A: ");
Serial.println(packet.A);
}
delay(50);
}

Receiver code example:

//Autor: Martin Chlebovec (martinius96)
//Web: http://arduino.clanweb.eu/

#include <SPI.h>
#include "RF24.h"
#define CE 4
#define CS 3
RF24 nRF(CE, CS);

typedef struct {
int T;
float A;
} dataPacket;

byte adresaPrijimac[] = "prijimac00";
byte adresaVysilac[] = "vysilac00";
void setup() {
Serial.begin(9600);
nRF.begin();
nRF.setDataRate( RF24_250KBPS );
nRF.setPALevel(RF24_PA_LOW);
nRF.openWritingPipe(adresaPrijimac);
nRF.openReadingPipe(1, adresaVysilac);
nRF.startListening();
}

void loop() {
dataPacket packet;
if ( nRF.available()) {
while (nRF.available()) {
nRF.read(&packet, sizeof(dataPacket));
Serial.print("Prijata hodnota T: ");
Serial.println(packet.T);
Serial.print("Prijata hodnota A: ");
Serial.println(packet.A);
}
nRF.stopListening();
packet.T = 200;
packet.A = 6.28;
nRF.write(&packet, sizeof(dataPacket));
nRF.startListening();
}
}
3

augustinto:
With the following code ...

Please include short programs in your Post using the code button </> so we don't have to download them,

Sending a struct should be straightforward - just like sending an array.

MyStruct myData;

radio.write(&myData, sizeof(myData));

and you should receive the data into an equivalent struct.

...R
Simple nRF24L01+ Tutorial

4

Thanks Robin2 and martinius96, I'm new here. Sorry for not using the code button.
Gonna try again with your tips and I'll get back to you with the results.